When Flea Shampoo Hurts More Than It Helps
The PawPurity team has come across countless dogs suffering from unusually sensitive skin. Often, pet parents don’t realize is that these sensitivities are often caused—or worsened—by the shampoos they’re using. Many commercial flea shampoos contain ingredients that are far too harsh for a dog’s delicate skin.
Most of these shampoos contain the wrong pH levels, synthetic chemicals, harsh surfactants that strip away natural oils, and petroleum-based artificial fragrances that do more harm than good.
It’s important to remember that a dog’s skin is much thinner than ours—just 1 to 5 millimeters thick compared to 10 to 15 millimeters in humans. That means dogs absorb topical products far more easily. If a shampoo irritates your dog externally, it can impact them internally as well. And since dogs groom themselves by licking, those harmful ingredients can end up in their mouth and their body.
Toxic Ingredients in Flea & Tick Shampoos That Can Harm Dogs
Pyrethrins
Pyrethrins are natural insecticides derived from chrysanthemum flowers. However, when concentrated in flea shampoos, they can cause serious adverse reactions in dogs. Exposure may lead to skin irritation, excessive drooling, vomiting, tremors, or even seizures, particularly in small dogs or puppies.
Pyrethroids
These are synthetic counterparts to pyrethrins. They are even more potent and longer-lasting. While effective at killing fleas and ticks, they are known neurotoxins. In dogs, they can cause itching, restlessness, excessive salivation, and neurological symptoms such as shaking or disorientation. They are also extremely toxic to cats, making cross-contamination a serious concern in multi-pet households.
Permethrin
Permethrin is a synthetic insecticide commonly found in topical flea products. It is particularly hazardous when absorbed or ingested. Even mild exposure can cause vomiting, diarrhea, muscle tremors, or loss of coordination, especially in dogs with sensitivities or weakened immune systems.
DEET
This chemical is found in many insect repellents. Sometimes they are added to flea products despite not being approved for veterinary use. Ingestion or skin absorption can result in vomiting, drooling, ataxia, and behavioral changes in dogs.
Citronella
Citronella is often marketed as a “natural” repellent, but this is misleading. It's often positioned as a safe alternative. However, when used in high concentrations, it has been shown to cause digestive upset, muscle weakness, and even seizures in dogs if ingested or absorbed in large quantities.
Artificial fragrances and dyes
While artificial fragrances and dyes may give your dog a pleasant scent and a fun look, they don't offer any health benefit and are common allergens. These synthetic additives can trigger itching, rashes, and dermatitis, especially in dogs with sensitive skin or existing allergies.
Harsh surfactants
Sodium lauryl sulfate (SLS) and sodium laureth sulfate (SLES) are commonly used to create lather but are known to strip the skin’s natural oils. This weakens the skin barrier, making it more prone to irritation, dryness, and secondary infections. As it is, your pet's skin barrier is quite thin and vulnerable to absorbtion of shampoos.
Preservatives
Be aware: preservatives such as DMDM hydantoin and diazolidinyl urea are formaldehyde-releasing agents. While they’re often used to extend shelf life, they’ve been linked to allergic reactions and long-term health risks, including potential carcinogenic effects. For a full list of preservatives to avoid in pet shampoos, download our guide in the blog Best Dog Shampoo for Skin Conditions.
PawPurity's Suggestions
Living in an area where fleas and ticks are common, it’s essential to protect your dog. But just as important is ensuring that the shampoo you’re using is gentle enough for dogs with sensitive skin and has no toxins or harsh chemicals.
Zoey - Victim of Unsafe Flea & Tick Repellents
While living in California, using a flea and tick repellent was routine. But one of those treatments—a vet-recommended spot-on product—took the life of my 7-year-old dog. At the time, there were no safe, natural options. You trusted what was on the market. That experience changed everything. It’s why PawPurity exists. Today, there are choices. Please—whatever you do—choose to go natural.
PawPurity’s Flea & Tick Shampoo: Safe for Sensitive Skin
PawPurity’s Flea & Tick Shampoo was created specifically for dogs with delicate, irritated, or allergy-prone skin. It’s natural, pH-balanced for dogs, and free of harsh chemicals, pesticides, sulfates, and synthetic fragrances—all of which are common triggers for skin problems.
Instead, it’s formulated with gentle olive, argan, and coconut-based cleansers, along with aloe vera, calendula, red clover, and yucca root to calm inflammation and heal flea bite damage. It uses essential oils like cedarwood, lemongrass, and honeysuckle to repel pests safely without harming your dog or disrupting their natural skin barrier.
It’s safe, non-toxic, and gentle enough to use regularly. But most importantly...it was made with purpose—to protect dogs naturally, especially those who need it most.
Looking for a shampoo that’s as safe as it is effective? Try PawPurity’s Flea & Tick Shampoo and experience the difference natural care makes.
